On Wednesday 11 November 2009 06:41:58 Farkas Levente wrote:
On 11/11/2009 11:53 AM, Richard W.M. Jones wrote:
On Wed, Nov 11, 2009 at 10:14:21AM +0000, Richard W.M. Jones wrote:
echo input | time cpio --quiet -o -H newc > /path/to/fs/output
Update: I found the -C option that lets me specify the blocksize, and raising it to something sensible (65536) shows major improvements in performance for all filesystems.
echo input | time cpio -C 65536 --quiet -o -H newc > /path/to/fs/output
tmpfs 0.77 s x 1.0 ext2 1.12 s x 1.5 xfs 1.66 s x 2.1 ext3 2.58 s x 3.4 ext4 5.59 s x 7.3 <----
The new times are:
tmpfs 0.20 s x 1.0 ext2 0.30 s x 1.5 xfs 0.41 s x 2.1 ext3 0.57 s x 2.9 ext4 0.44 s x 2.2
imho it's still a bug. wouldn't somehow rise the default or make the writes buffered or ... since the current situation is not correct.
I am not sure if this is related or not ...
During the F12 development cycle, I have done a number of installs on both bare hardware and qemu-kvm guests.
In all cases, I have formatted the root ("/") partition as ext4. I have noticed that formatting the partition for ext4 seems to take considerably more wall-clock time for ext4 partitions than my previous experience with ext3 partitions.
I do not know if this is because ext4 "formatting" needs to do a lot more work than ext3 or if there is a performance issue.
Gene